Slide projectors with a chute to feed the slides to the projection gate under the effect of gravity and with a driven arm to move the slide out of the upper opening of the chute are already known. Such projectors are frequently operated in conjunction with a circular tray mounted on top of the projector which has slide compartments open on the underside and which can be aligned with the chute, see U.S. Pat. No. 3,276,314.
A known slide projector of the generic type, see DE-AS 1 285 205, offers the user the possibility of projecting slides automatically without previously having to load the slides into a slide tray. With this known projector it is only necessary to place a stack of slides which are in contact with one another into the one storage chamber of the stack loader which is mounted above the chute instead of a tray. When the slides have been projected, the stack of slides can then be taken out of the second storage chamber of said loader.
Although this known projector relieves the user of the necessity for loading the slides into a tray, a projector of this type has certain limitations with respect to its universal applicability. For example, it is not possible to project the slides "backwards", as slides already projected and loaded into the second storage chamber cannot be projected a second time without being taken out of the second storage chamber and placed into the first storage chamber again. The above known projector is not suitable either for the projection of slides of different thicknesses, for example slides with different mounts.